uni'wissen 01-2012_ENG

What do driving a car in the fog and viewing thick objects through a microscope have in common? – The two situations both present the same problem: The light is scattered. In the first case, fog droplets prevent the car’s headlights from penetrating through to obstacles and thus from sufficiently illuminating them. In the same way, thick collections of thousands of cells scat­ ter the light from the illuminator of optical micro­ scopes such as those used in modern cell biology. In fact, the scattering is so strong that cells of the object under observation located fur­ ther from the light source are hardly visible at all. Illuminating Remote Corners The Physicist Alexander Rohrbach Is ­Developing a New Type of Microscope with Self-Reconstructing Laser Beams That Enables Better Images Alexander Rohrbach, professor of bio- and nanophotonics, has succeeded in clearly reducing the undesired deflection and scattering of the light inside the object. Together with his research group at the Department of Microsystems Engi­ neering of the University of Freiburg, he is devel­ oping a new and innovative microscopy method based on self-reconstructing laser beams. This development is a boon for scientists studying comparatively large specimens with a thickness of up to one millimeter. Up until now, microscopy has been unable to properly illumi­ by Annette Kollefrath-Persch 20